Purpose: :
The cone photoreceptor cyclic nucleotide-gated (CNG) channelis a heterotetramer composed of two alpha and two beta subunitsand plays a fundamental role in phototransduction. Achromatopsiais an inherited autosomal recessive retinal disorder characterizedby a lack of cone function and frequently caused by mutationsin the CNGA3. We previously identified a minimal promoter regionof the CNGA3 gene located upstream of exon 1, therefore examinationof transcription factors binding to the CNGA3 promoter may provideinsights into the mechanisms of cone specific gene expressionand reveal important sequences that should be included in mutationscreening studies.